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Isotherm Jacket

Whether backcountry skiing or ice climbing, the Isotherm Jacket is built for the active purists. The lightweight 20-denier Pertex® Quantum® down-proof fabric is filled with Polartec® Alpha® insulation for warmth when you're on the move; breathable Polartec® Power Stretch® panels allow uninhibited movement. Layer this incredibly lightweight puffy over a midlayer for warmth when you're on the move.

*Trail-to-Town pants have specific waist sizes.**Inseam lengths above are average size lengths. Some pants are available in additional inseam lengths and will display on the product page.

Rated 5 out of
5 by
Kyle_C from
Fully featured, warm and very breathableI actually use the older version (Very similar except the Power Stretch Pro part being Softshell) for trail running. Some say it may be overkill but I would say it fits perfectly into cold/ extreme cold weather running (< -10 °C). Shell is windproof and the insulation is warm, the mesh liner makes is very breathable, and the reason I am saying this is that I can physically grab on ice pellets in the insulation part which are in fact my frozen sweat. The softshell part is also optimal in terms of warmth but won't overheat my arms. Last but not least, the pockets are awesome.